Follow-me reverts from Float to Absorb

Started by malkierian, September 05, 2021, 07:07:21 PM

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malkierian

I have 6 classics tied together in follow-me mode, with one classic, which has the Whizbang connected to it, as the master. However, I've noticed that, despite the ending amps being set to 2% of the AH rating, the master goes into float, but it keeps reverting to absorb before the rest of the classics can change over. Often 3 or 4 of them will get to bulk, but only one gets to float before the master reverts back to absorb, thus putting the rest back into absorb. Is there something I can do about that?
1st System: 12.5kw on 5 Classics (3 150s, 2 250s), 1 classic 250 with wind turbine, 2 stacked Magnum 4024PAE inverters.

2nd System: 1250W solar on 1 Classic 150, two DIY3024 running separate breaker boxes, one hooked up to Magnum output for AC charging.

Vic

Hi malkierian,

Please check that all of the Following Classics,   are still set to Follow,  and that all of the Classics have their blue LEDs,  flashing appropriately.

Also,  would not hurt to check that the Firmware versions in all Classics,  match.

Did this set of Classics ever work the way you wanted them(to)?

Just guessing,  to try to get things rolling  ...

FWIW,   Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

malkierian

I've never quite been able to figure out how to check the firmware version on them.

It seemed to work back when I had 4, but I didn't have proper charging settings set up for a multi-classic array with a WBJr. Once I disabled the Ending Amps function on all but the master Classic
(where I switched it to using the WBJr reading at 2% of the bank's capacity), this problem presented itself.

Also, the blue LEDs are supposed to blink once, slowly, every few seconds, correct? the weird thing is, sometimes they blink slowly, sometimes they blink quickly. Haven't been able to figure out what that meant, either.
1st System: 12.5kw on 5 Classics (3 150s, 2 250s), 1 classic 250 with wind turbine, 2 stacked Magnum 4024PAE inverters.

2nd System: 1250W solar on 1 Classic 150, two DIY3024 running separate breaker boxes, one hooked up to Magnum output for AC charging.

boB

When the LED blinks quickly, it means the packet was received correctly.  Sometimes it will blink slower (stay on longer) which means it did not receive the packet properly (as I remember) but is normal as long as the LED(s) do not blink slowly ALL the time.

The Classic with the WB Jr. on it may be seeing the battery current go below the ending amps but because the Classic is in the Absorb cycle, it tries to keep the battery voltage sitting there until it can go to Float and take the other Classics with it through the F-Me.  Like you said.

But just when it should stay put, the Classic will regulate and when the PV input voltage is much higher than the battery voltage, it is not quite smooth enough.   The Classic requires that current to stay below the ending-amps setting for around 1 minute.   I think the problem is that when it regulates, sometimes the jump will bring the voltage up slightly and then it will reset that 1 minute counter.

If the current drops down even further below the ending amps, it should eventually get around to taking the other Classics with it into Float.

This may be a bug.  What you can try for now is to increase the ending-amps a bit.  Or use the timed Absorb instead ?

Will be thinking about this.  Someone may come in with another idea though.

boB

K7IQ 🌛  He/She/Me

Vic

To check the Firmware versions of Classics and MNGPs,  press the Left,  small round button on the MNGP,  about six times,  and note the version numbers on the MNGP screen.

Also,  from the Local App,  on the main status screen of the LA dashboard,  click the "Info" button,  on each Classic,  to see the FW info.

Vic
Off Grid - Sys 1: 2ea SW+ 5548, Surrette 4KS25 1280 AH, 5.25 KW PV, Classic 150,WB, Beta Barcelona, Beta KID
Sys 2: SW+ 5548s, 4KS25s, 5.88 KW PV, 2 ea. Classic 150, WB, HB CC-needs remote Monitoring/Control, site=remote.
 MN Bkrs/Bxs/Combiners. Thanks MN for Great Products/Svc/Support&This Forum!!

ClassicCrazy

from midnite knowledge base
http://www.midniteftp.com/support/kb/faq.php?cid=1

CLASSIC - F-ME - How to setup Classics in true MASTER/SLAVE Mode
Last Updated 6 months ago

The Follow-Me concept does not embrace Master/Slave topology.  With a few "tweaks" you can have a simple master/slave setup which I find personally works better.  Below I will tell you how it's done and explain how it works. (this may have limited benefits for 2 Classics)

First, we need to pick a Classic to be our MASTER Controller.  It will be called the "BTS MASTER"  Why is this?  Because one of the neat advantages of having F-Me setup is we can use a single BTS (Battery Temperature Sensor) and not need 2 or 3 or 4 or xx sensors and all that extra wire tied up somewhere.  The BTS-NET option in the Classic allows a single BTS to provide data to all Classics.  The BTS-NET is also a easy way to check that the cables are good and the F-Me network is functional.

1 - Pick a BTS MASTER Classic, install the BTS and set it to MASTER in the TWEAKS MENU under BTS-NET (page down to get to the sub-menu)
All other Classics get this set to FOLLOW.  This should be self explanatory to most seasoned Solar Installers & Electricians.

2 - If the Whizbang Jr SHUNT Option is going to be installed, install it in this Classic. This Classic will be the "MASTER of all things". This will be required for ENDAMPS control.

3 - All charging voltages get set the same.  The only thing we set differently is CHARGE TIMES.

4 - Set your needed ABSORB TIME in the MASTER, the rest (SLAVES) get set with that plus 10 minutes.  See, what this does it lets the MASTER decide when to send everyone to FLOAT.  If for some reason F-Me breaks, all that happens is the SLAVES stay in Absorb for an extra 10 minutes.

A GF or Ground Fault seems to only shut down the offending Classic so we should not need to worry about down-stream Classics sending data back around. AF or Arc Fault seems to exhibit the same behavior, at least on my 5 Classic system.

There is a misconception that ABSORB is a F-me function, it is not.  ALL Classics MUST reach their ABSORB voltage independently.  ANY Classic that fails to maintain the programmed Absorb Voltage for 90 seconds with be forced BACK into BULK and this mode will be propagated from this Classic to the last in line. Hopefully this provides enough power to get back into ABSORB.

If using ENDAMPS and REBULK set it up ONLY in the MASTER, let it decide since it has the WhizbangJR (Needed for proper ENDAMPS Operation)  Don't use ENDAMPS unless you have a WBjr installed & setup to use the SHUNT.

I have removed the Follow-Me cable from the LAST Classic to the FIRST on my system.  Everything goes ONE-WAY from the MASTER on the LEFT to the others on the RIGHT or Down-Stream.  This seems to be working, this stops the "SLAVES" from sending modes back to the MASTER flipping it.  I like it better but it is not a Midnite official mode of operation but is supported now.  I like the MASTER to be in total control.  Use at your own risk...

Hope this helps, Jim Parish, MNS Tech Support
system 1
Classic 150 , 5s3p  Kyocera 135watt , 12s Soneil 2v 540amp lead crystal for 24v pack , Outback 3524 inverter
system 2
 5s 135w Kyocero , 3s3p 270w Kyocera  to Classic 150 ,   8s Kyocera 225w to Hawkes Bay Jakiper 48v 15kwh LiFePO4 , Outback VFX 3648 inverter
system 3
KID / Brat portable

boB


I am wondering...   Are all of the Classics the same voltage ratings ?   i.e.   All 150s or 200s or 250s ?

If not the same, which one is the WB Jr. connected to ?

Maybe connecting the WB Jr. to another Classic might help.

K7IQ 🌛  He/She/Me

malkierian

Quote from: boB on September 06, 2021, 01:41:03 AMThe Classic with the WB Jr. on it may be seeing the battery current go below the ending amps but because the Classic is in the Absorb cycle, it tries to keep the battery voltage sitting there until it can go to Float and take the other Classics with it through the F-Me.  Like you said.

But just when it should stay put, the Classic will regulate and when the PV input voltage is much higher than the battery voltage, it is not quite smooth enough.   The Classic requires that current to stay below the ending-amps setting for around 1 minute.   I think the problem is that when it regulates, sometimes the jump will bring the voltage up slightly and then it will reset that 1 minute counter.

If the current drops down even further below the ending amps, it should eventually get around to taking the other Classics with it into Float.
I sat there for 5 minutes watching the first two Classics hit float, but the third one always refused to follow. Turns out that it was set to master as well, but it still wouldn't follow after I set it to follow. I'm going to restart them tonight when I don't need them to charge anything and see if it fixes it tomorrow.

Quote from: ClassicCrazy on September 06, 2021, 11:35:52 AM
from midnite knowledge base
http://www.midniteftp.com/support/kb/faq.php?cid=1

CLASSIC - F-ME - How to setup Classics in true MASTER/SLAVE Mode
Last Updated 6 months ago

The Follow-Me concept does not embrace Master/Slave topology.  With a few "tweaks" you can have a simple master/slave setup which I find personally works better.  Below I will tell you how it's done and explain how it works. (this may have limited benefits for 2 Classics)

First, we need to pick a Classic to be our MASTER Controller.  It will be called the "BTS MASTER"  Why is this?  Because one of the neat advantages of having F-Me setup is we can use a single BTS (Battery Temperature Sensor) and not need 2 or 3 or 4 or xx sensors and all that extra wire tied up somewhere.  The BTS-NET option in the Classic allows a single BTS to provide data to all Classics.  The BTS-NET is also a easy way to check that the cables are good and the F-Me network is functional.

1 - Pick a BTS MASTER Classic, install the BTS and set it to MASTER in the TWEAKS MENU under BTS-NET (page down to get to the sub-menu)
All other Classics get this set to FOLLOW.  This should be self explanatory to most seasoned Solar Installers & Electricians.

2 - If the Whizbang Jr SHUNT Option is going to be installed, install it in this Classic. This Classic will be the "MASTER of all things". This will be required for ENDAMPS control.

3 - All charging voltages get set the same.  The only thing we set differently is CHARGE TIMES.

4 - Set your needed ABSORB TIME in the MASTER, the rest (SLAVES) get set with that plus 10 minutes.  See, what this does it lets the MASTER decide when to send everyone to FLOAT.  If for some reason F-Me breaks, all that happens is the SLAVES stay in Absorb for an extra 10 minutes.

A GF or Ground Fault seems to only shut down the offending Classic so we should not need to worry about down-stream Classics sending data back around. AF or Arc Fault seems to exhibit the same behavior, at least on my 5 Classic system.

There is a misconception that ABSORB is a F-me function, it is not.  ALL Classics MUST reach their ABSORB voltage independently.  ANY Classic that fails to maintain the programmed Absorb Voltage for 90 seconds with be forced BACK into BULK and this mode will be propagated from this Classic to the last in line. Hopefully this provides enough power to get back into ABSORB.

If using ENDAMPS and REBULK set it up ONLY in the MASTER, let it decide since it has the WhizbangJR (Needed for proper ENDAMPS Operation)  Don't use ENDAMPS unless you have a WBjr installed & setup to use the SHUNT.

I have removed the Follow-Me cable from the LAST Classic to the FIRST on my system.  Everything goes ONE-WAY from the MASTER on the LEFT to the others on the RIGHT or Down-Stream.  This seems to be working, this stops the "SLAVES" from sending modes back to the MASTER flipping it.  I like it better but it is not a Midnite official mode of operation but is supported now.  I like the MASTER to be in total control.  Use at your own risk...

Hope this helps, Jim Parish, MNS Tech Support
Thanks for this, I tried disconnecting the return in the master, but that just made the first two go into Resting mode, while the rest were some hodgepodge of Bulk and Absorb. Again, this was before discovering the third one in the line had somehow turned into master again. If the restart overnight doesn't fix it, I'll try that again with the change in follow-me mode on the third classic.

Quote from: boB on September 06, 2021, 01:55:19 PM

I am wondering...   Are all of the Classics the same voltage ratings ?   i.e.   All 150s or 200s or 250s ?

If not the same, which one is the WB Jr. connected to ?

Maybe connecting the WB Jr. to another Classic might help.
I do have a mix. I have three 150s, which are the first three in the string (and the WBJr is connected to the first 150), then a 250 (wind generator), then two 200s.
1st System: 12.5kw on 5 Classics (3 150s, 2 250s), 1 classic 250 with wind turbine, 2 stacked Magnum 4024PAE inverters.

2nd System: 1250W solar on 1 Classic 150, two DIY3024 running separate breaker boxes, one hooked up to Magnum output for AC charging.

australsolarier

i have 4 midnite 150 in follow mode. every so often, maybe every 6 months (i am not always around to watch it), one of the midnite refuses to forward the float signal. the midnite with the whiz bang jr shunt then gets triggered back to bulk, sends out the float signal to the recalcitrant midnite and the whole thing starts again until manual intervention or time out is reached.
it is just one of the minor things that sort of blips up.
personally i would prefer a master/slave situation where the master orders ALL the slaves not just the one next in row.
having all said that, there is an extraordinary amount of bundled wires parallel to the slave/master telephone cable and this could possibly have an influence. i am not quite sure, but i think it is the same midnite that is recalcitrant.

also pressing the status button rapidly has changed 2x the contrast settings, has changed "sync"  and in one of the midnite brings up the alarm. as a matter of fact i am reluctant to use the mng because of good knows what setting i changes unknowingly.